CN103586655B - A kind of machining process of large diameter thin wall part - Google Patents
A kind of machining process of large diameter thin wall part Download PDFInfo
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- CN103586655B CN103586655B CN201310556370.9A CN201310556370A CN103586655B CN 103586655 B CN103586655 B CN 103586655B CN 201310556370 A CN201310556370 A CN 201310556370A CN 103586655 B CN103586655 B CN 103586655B
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- 238000003754 machining Methods 0.000 title claims abstract description 51
- 238000000034 method Methods 0.000 claims abstract description 25
- 229910000743 fusible alloy Inorganic materials 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims abstract description 7
- 229910045601 alloy Inorganic materials 0.000 claims description 29
- 239000000956 alloy Substances 0.000 claims description 29
- 238000002844 melting Methods 0.000 claims description 14
- 230000008018 melting Effects 0.000 claims description 14
- 238000005266 casting Methods 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 238000002679 ablation Methods 0.000 claims description 6
- 239000010935 stainless steel Substances 0.000 claims description 4
- 229910001220 stainless steel Inorganic materials 0.000 claims description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 3
- 229910052797 bismuth Inorganic materials 0.000 claims description 3
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 abstract 1
- 238000010002 mechanical finishing Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000003014 reinforcing effect Effects 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Jigs For Machine Tools (AREA)
Abstract
The invention provides a kind of machining process of large diameter thin wall part, described method for part be the much larger large diameter thin wall part of a kind of outside diameter relative wall thickness, and this part is made up of the material that quality is very soft, traditional processing technology is difficult to processing, for the problems referred to above, the invention provides the step increasing the thickness of part by filling low-melting alloy, being convenient to machining with the rigidity increasing part.Said method of the present invention by thin-walled parts fill low-melting alloy, improve the machining machinability of part, eliminate and avoid adding man-hour produce pinching deformation and stress deformation, ensure that wall thickness dimension and flatness processing qualified.
Description
Technical Field
The invention relates to a machining method of an aviation part, in particular to a machining method of a part with a diameter larger than the wall thickness, which is suitable for machining the aviation part which is made of softer material, has thin wall thickness, does not have reinforcing ribs and has high flatness requirement.
Background
The area of a web plate of a diffuser sealing cover part in aviation equipment is large, the wall thickness is very thin and has no reinforcing ribs, the wall thickness is only 1-1.5mm, the selected material is often stainless steel (such as PH 17-4) with good weldability and is soft, the structure of the diffuser sealing cover part is shown in figures 1 and 2, and the stereo structure of two side view angles of the large-diameter thin-wall part is shown in a schematic diagram. The material selected for the part has almost no processing rigidity strength under the thickness of 1.5mm, and the conventional machining method can generate clamping deformation and stress deformation during processing, but the requirement on the flatness of the web plate is high.
For example, when the part is subjected to a finish turning process, a special clamp is adopted for clamping, double-pressure plate switching type compression is adopted, end face machining is completed in a segmented mode, the part has clamping deformation and stress deformation, the wall thickness machining of the web is extremely unstable and easy to be out of tolerance, the flatness requirement of the web reaches below 0.05mm, machining is difficult to guarantee, the repair rate is above 40%, and repeated repair is carried out, clamping positioning of the lower process is seriously influenced, the production cycle is prolonged, and the delivery cycle and the number of components are limited.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a method for machining a large-diameter thin-walled part, so as to reduce or avoid the aforementioned problems.
In order to solve the technical problem, the invention provides a machining method of a large-diameter thin-wall part, wherein the part is an annular structure with the outer edge diameter of 200-500mm, the width from a central hole to the outer edge of the annular structure is 20-80mm, the wall thickness of the part is 1-1.5mm, the part is made of stainless steel (such as AMS5622 or AMS 5643), and the flatness requirement of a web plate after machining is less than 0.05mm, the machining method is used for performing mechanical finish machining on the part after molding, and comprises the following steps:
providing a horizontally placed die, wherein the die is provided with an annular groove, and the diameter of the inner side wall of the annular groove is smaller than that of the central hole of the part;
placing the side, which needs to be subjected to mechanical finish machining, of the part downwards in an annular groove of the mold, wherein the outer edge of the part is tightly abutted against the outer side wall of the mold, and the overall height of the part is lower than the depth of the annular groove of the mold;
pouring a low-melting-point alloy on the upper surface of the part, so that the low-melting-point alloy is filled between the part and the mold and is attached to the upper surface of the part after being cooled;
taking the part out of the die, then installing the part on a first machining clamp, and machining one side attached with the low-melting-point alloy to form a supporting surface and a positioning surface;
the part is arranged on a second clamp by taking the supporting surface and the positioning surface as references, and the surface of the part needing to be subjected to mechanical finish machining is subjected to mechanical finish machining;
and melting the low-melting-point alloy attached to the machined part, so as to obtain the machined part.
Preferably, the diameter of the inner side wall of the annular groove is 0.1-0.2mm smaller than the diameter of the central hole of the part.
Preferably, the thickness of the low melting point alloy after casting is 10-20 mm.
Preferably, the low-melting-point alloy is an alloy containing bismuth, lead and tin, and the melting point is lower than 90 degrees.
Preferably, the ablation step uses water bath ablation, and the temperature of the water bath is 90-100 degrees.
According to the method, the thin-wall part is filled with the low-melting-point alloy, so that the machining machinability of the part is improved, the clamping deformation and the stress deformation generated in the machining process are eliminated and avoided, and the qualified machining of the wall thickness and the flatness is ensured.
Drawings
The drawings are only for purposes of illustrating and explaining the present invention and are not to be construed as limiting the scope of the present invention. Wherein,
FIGS. 1 and 2 show schematic perspective views of two side views of a large-diameter thin-walled part according to the present invention;
FIG. 3 shows a schematic machined cross-sectional view of a large diameter thin-walled part of the present invention according to one embodiment of the present invention;
FIG. 4 is a cross-sectional view of the machined seating and locating surfaces of the part of FIG. 3 after increasing the thickness thereof;
FIG. 5 is a schematic illustration of a machine finishing of a part using the seating and locating surfaces of FIG. 4 as a datum.
Detailed Description
In order to more clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will now be described with reference to the accompanying drawings. Wherein like parts are given like reference numerals.
As mentioned in the background section, the present invention relates to a method which can be used for the mechanical finishing of a thin-walled part 1 of large diameter as shown in fig. 1 and 2, as far as the previous process of forming the part 1 is prior art, and can be carried out by existing machining means, such as casting, stamping and the like, which are not essential to the invention and therefore not described in detail herein, and the invention is only claimed for the mechanical finishing of the end faces and/or the webs 12 of the part 1.
Since the method of machining according to the invention is directed to a part 1 of a specific shape and material, it is necessary to specify: the part 1 is an annular structure with the outer edge 13 of 200-500mm in diameter, the width between the central hole 14 and the outer edge 13 of the annular structure is 20-80mm, the wall thickness of the part is 1-1.5mm, the part is made of stainless steel (such as AMS5622 or AMS 5643), and the flatness of the processed web plate 12 of the part is required to be less than 0.05 mm. As can be seen from the above description, the component 1 according to the present invention is a large-diameter thin-walled component with a large outer diameter relative to a large wall thickness, and the component 1 is made of a soft material and has a central hole 14 in the center, when it is necessary to perform mechanical finishing on the web 12 and/or the end face, especially when the requirement on the flatness of the web 12 after machining is high, the conventional machining process needs to fix and position the component by using a clamp, however, as described in the background section, due to the limitation of the special structure and material of the component 1 according to the present invention, the component may have clamping deformation and stress deformation when fixing and positioning the clamp, the web wall thickness machining is unstable, and since the web 12 is thin and soft, the end face deformation is serious, and there is basically no way to perform mechanical finishing.
Therefore, the invention provides a machining method of a large-diameter thin-wall part based on the problems, which is used for performing mechanical finishing after the part is formed so as to eliminate and avoid clamping deformation and stress deformation generated during machining of the part 1 and ensure that the wall thickness dimension and the flatness are qualified during machining.
The machining method of the present invention is described in detail below with reference to fig. 3-5, wherein fig. 3 shows a schematic machining cross-sectional view of a large-diameter thin-walled part of the present invention according to one embodiment of the present invention, with the following steps:
firstly, providing a horizontally placed mould 2, wherein the mould 2 is provided with an annular groove 21, and the diameter of the inner side wall 22 of the annular groove 21 is smaller than that of the central hole 14 of the part 1;
then, the side of the part 1 to be mechanically finished is placed downwards in the annular groove 21 of the die 2, the outer edge 13 of the part 1 is tightly abutted against the outer side wall 23 of the die 2, and the overall height of the part 1 is lower than the depth of the annular groove 21 of the die 2.
Thereafter, a low melting point alloy 4 is poured on the upper surface of the part 1 such that the low melting point alloy 4 is filled between the part 1 and the mold 2, and is attached to the upper surface of the part 1 after cooling, as shown in fig. 3.
In the three steps, a mould 2 is provided, the part 1 is placed in the mould, and a layer of low-melting-point alloy 4 is attached to one side which does not need to be machined in a casting mode, so that the thickness of the part 1 is artificially increased, and the part is not a thin-wall part any more. The key point of the invention is therefore the filling of the low-melting alloy, the machinability of the part 1 being enhanced by casting the low-melting alloy 4, so that the clamping deformations and stress deformations of the part 1 occurring in the subsequent machining are negligible. In a preferred embodiment, the diameter of the inner side wall 22 of the annular groove 21 is 0.1-0.2mm smaller than the diameter of the central hole 14 of the part, and in another preferred embodiment, the thickness of the low melting point alloy 4 after casting is 10-20mm, so that the added thickness is much larger than the thickness of the web 12 of the part 1, and the rigidity of the part 1 is greatly enhanced. In a further preferred embodiment, the low melting point alloy 4 is an alloy containing bismuth, lead and tin, and the melting point is lower than 90 degrees, and the advantage of using the low melting point alloy 4 is obvious, namely, the casting and processing are convenient, and the removal of the low melting point alloy 4 in the subsequent processing process is also convenient.
Thereafter, the part 1 is removed from the die 2 and then mounted on a first machining jig (not shown), and the side to which the low-melting alloy 4 is attached is machined to form a bearing surface 41 and a positioning surface 42 on the low-melting alloy 4, as shown in fig. 4, which is a cross-sectional view of the bearing surface and the positioning surface after the part 1 is increased in thickness.
Since the surface of the low melting point alloy 4 is uneven after the thickness of the part 1 is increased by filling the low melting point alloy 4 in the past, but since the rigidity of the part 1 is greatly increased after the thickness is increased, the part 1 can be clamped by a common simple jig (first jig) to machine the seating surface 41 and the positioning surface 42.
Thereafter, the component 1 is mounted on a second fixture (not shown) with reference to the abutment surface 41 and the positioning surface 42, and a surface of the component 1 to be mechanically finished is mechanically finished, as shown in fig. 5, which is a schematic view of the mechanical finishing of the component 1 with reference to the abutment surface 41 and the positioning surface 42 in fig. 4.
In the step, as the side of the part 1 which needs to be processed is exposed and can not be clamped, the support surface 41 and the positioning surface 42 are processed on the low-melting-point alloy 4 and then used as the basis for clamping and positioning without step-by-step processing, repeated positioning is not needed, and the precision of mechanical processing is greatly increased. In addition, after the rigidity is increased, the part 1 can be clamped by a common simple clamp (a second clamp), and the part is not clamped by a special clamp, so that the processing cost is reduced.
And finally, the low-melting-point alloy 4 attached to the machined part 1 is melted off, and the machined part 1 can be obtained. In a preferred embodiment, the ablation step uses water bath ablation, the temperature of the water bath being 90-100 degrees. The step corresponds to the characteristics of the low-melting-point alloy, the low-melting-point alloy 4 can be easily removed without causing any damage to the part 1 by adopting a water bath ablation mode, namely the advantage that the rigidity of the part 1 is increased by easily pouring the low-melting-point alloy 4 can be utilized, and the removal is also convenient, which is another great advantage of the invention.
It should be appreciated by those of skill in the art that while the present invention has been described in terms of several embodiments, not every embodiment includes only a single embodiment. The description is given for clearness of understanding only, and it is to be understood that all matters in the embodiments are to be interpreted as including technical equivalents which are related to the embodiments and which are combined with each other to illustrate the scope of the present invention.
The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. Any equivalent alterations, modifications and combinations can be made by those skilled in the art without departing from the spirit and principles of the invention.
Claims (5)
1. A machining method for a large-diameter thin-wall part is an annular structure with the outer edge of 200-500mm in diameter, the width between a central hole of the annular structure and the outer edge of the annular structure is 20-80mm, the wall thickness of the part is 1-1.5mm, the part is made of stainless steel materials, the flatness requirement of a web plate of the part after machining is less than 0.05mm, the machining method is used for performing mechanical finish machining on the part after forming, and the machining method comprises the following steps:
providing a horizontally placed die, wherein the die is provided with an annular groove, and the diameter of the inner side wall of the annular groove is smaller than that of the central hole of the part;
placing the side, which needs to be subjected to mechanical finish machining, of the part downwards in an annular groove of the mold, wherein the outer edge of the part is tightly abutted against the outer side wall of the mold, and the overall height of the part is lower than the depth of the annular groove of the mold;
pouring a low-melting-point alloy on the upper surface of the part, so that the low-melting-point alloy is filled between the part and the mold and is attached to the upper surface of the part after being cooled;
taking the part out of the die, then installing the part on a first machining clamp, and machining one side attached with the low-melting-point alloy to form a supporting surface and a positioning surface;
the part is arranged on a second clamp by taking the supporting surface and the positioning surface as references, and the surface of the part needing to be subjected to mechanical finish machining is subjected to mechanical finish machining;
and melting the low-melting-point alloy attached to the machined part, so as to obtain the machined part.
2. A machining method according to claim 1, characterized in that the diameter of the inner side wall of said annular groove is 0.1-0.2mm smaller than the diameter of the central hole of said piece.
3. A machining method according to claim 1, characterized in that the thickness of said low-melting alloy after casting is 10-20 mm.
4. The machining method according to claim 1, wherein the low-melting-point alloy is an alloy containing bismuth, lead, and tin, and has a melting point of less than 90 degrees.
5. The machining method of claim 4, wherein said ablating step uses a water bath ablation, the temperature of the water bath being 90-100 degrees.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310556370.9A CN103586655B (en) | 2013-11-11 | 2013-11-11 | A kind of machining process of large diameter thin wall part |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201310556370.9A CN103586655B (en) | 2013-11-11 | 2013-11-11 | A kind of machining process of large diameter thin wall part |
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| Publication Number | Publication Date |
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| CN103586655A CN103586655A (en) | 2014-02-19 |
| CN103586655B true CN103586655B (en) | 2016-03-23 |
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| CN201310556370.9A Active CN103586655B (en) | 2013-11-11 | 2013-11-11 | A kind of machining process of large diameter thin wall part |
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Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104057063B (en) * | 2014-05-23 | 2015-12-23 | 西安西航集团莱特航空制造技术有限公司 | A kind of low-melting alloy casting fixture of processing thin-walled part and using method thereof |
| CN104439919B (en) * | 2014-10-23 | 2017-07-07 | 山东大学 | Using the method for low-melting alloy secondary process thin-walled flexible member |
| CN105234637B (en) * | 2015-11-10 | 2019-08-02 | 上海斐赛轴承科技有限公司 | The production method of thin-wall bearing, its thin-walled inner ring/outer ring processing method and accurate flexible bearing |
| CN106141546A (en) * | 2016-08-28 | 2016-11-23 | 常德翔宇设备制造有限公司 | Welding tooling and the method for part die cavity filled by a kind of low-melting-point metal |
| CN106736693A (en) * | 2016-12-23 | 2017-05-31 | 贵州黎阳航空动力有限公司 | A kind of distortion-free processing method of thin-walled disk-like accessory |
| CN107813108B (en) * | 2017-10-27 | 2019-03-29 | 湖南南方通用航空发动机有限公司 | A kind of thin-walled parts processing method |
| CN109318498A (en) * | 2018-08-16 | 2019-02-12 | 深圳技师学院（深圳高级技工学校） | A kind of processing method of thin-walled parts |
| CN109500544B (en) * | 2018-10-16 | 2020-11-06 | 福建夜光达科技股份有限公司 | Thin and thick interval laminated manufacturing method of microstructure mold |
| CN109500660B (en) * | 2018-11-20 | 2021-01-22 | 中国航发贵州黎阳航空动力有限公司 | Measuring method and device in machining process of annular semi-closed thin-wall part |
| CN109759776B (en) * | 2019-03-29 | 2020-12-04 | 上海摩软通讯技术有限公司 | Method for manufacturing mesh component of mobile terminal and mobile terminal |
| CN113118703A (en) * | 2019-12-30 | 2021-07-16 | 杭州新剑机器人技术股份有限公司 | Machining method of thin-wall flexible gear part of harmonic reducer |
| CN113182786B (en) * | 2021-06-16 | 2022-08-30 | 上海睿昇半导体科技有限公司 | Machining method for thin-wall part in part |
| CN113927654B (en) * | 2021-08-27 | 2023-04-11 | 浙江先导精密机械有限公司 | Method for processing special-shaped thin-wall nylon piece |
| CN115401425A (en) * | 2022-09-30 | 2022-11-29 | 湖南飞宇航空装备有限公司 | Numerical control machining method for reinforced thin-wall metal part |
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Address after: 412002 Dong Jiaduan, Zhuzhou, Hunan Patentee after: China Hangfa South Industrial Co. Ltd. Address before: 412002 Dong Jiaduan, Zhuzhou, Hunan Patentee before: China Southern Airlines Industry (Group) Co., Ltd. |